1. Field of the Invention
This invention relates generally to the art of jointing sheet materials end to end and more particularly to a carpet construction provided with such a joint structure having a sliding clasp fastener.
2. Prior Art
It has been known in the art to butt-joint sheet materials by means of a sliding clasp fastener to provide a carpet or similar covering article, the sliding clasp fastener having a pair of stringer tapes each carrying along its inner longitudinal edge a row of interengageable fastener elements, and the stringer tapes being secured to reverse surfaces of opposed sheet materials adjacent to the abutting ends thereof whereby the adjacent sheet materials are butt-jointed together by closing the sliding clasp fastener by a slider movable along the fastener elements.
Such conventional joint structures have the disadvantage, however, that the coupled stringer tapes are oftentimes subjected to disengagement or mismeshing over a prolonged period of time. This difficulty arises out of the fact that these conventional joint structures were not provided with means for covering the coupled fastener elements to prevent foreign matters such as dust, dirt and grit from entering the spaces between the coupled fastener elements, which would in turn reduce the coupling strength of the fastener elements. This problem is serious particularly where these prior art joint structures are employed to butt-joint a plurality of sheet materials to provide a covering article for use outdoors such as a sheet of artificial lawn which is usually laid over the ground when the aforesaid foreign matters tend to adversely affect the manipulation of the slider to open and close the fastener and reduce the coupling strength of the fastener elements. Another disadvantage of such conventional joint structures is that they have not had any means for positively preventing the coupled fastener elements from moving in a direction transverse to the longitudinal axis of the sliding clasp fastener, which has further resulted in premature malfunction of the sliding clasp fastener.